STEAM TURBINE MODERNIZATIONS AT OPERATING FOSSIL POWER PLANTS: AN APPROACH TO MAXIMIZE EFFICIENCY AND OPTIMIZE COAL POWER PLANTS

In 2010, according to the International Energy Agency, coal fired power plants provided 49% of U.S. electricity - far higher than its 31.2% share of electric generating capacity - due to coal plants being run at higher capacity rates. This was due to the stable costs associated with coal as compared with the volatility of the natural gas markets. The remaining coal plants, which represents over 200GW of capacity, will likely require significant investment in air quality control systems (AQCS) and efficiency upgrades to survive. One of the fastest and most cost effective means to achieve greater energy efficiency and add capacity is through modernization of the steam turbine components. In many cases, modernized turbines can be manufactured and ready for installation in less than two years. Coal plants that will continue to operate for the next 20 or more years will likely have to have AQCS, which can consume up to 30% parasitic load (i.e. carbon capture). This load loss can be recovered in part through modernizing the original steam turbine with the latest technology. This paper will provide a commentary on trends and observations on the direction coal plants are taking and provide industry goals. An example of a steam turbine modernization will be discussed and the benefits it provides, such as improvement in performance, availability, reliability, life extension, and reduced life cycle costs. Opinions will be presented on the dynamic nature of the market.